Pipe TelephonyManager.getCallState through TelecommManager

* Add TelecommManager.getCallState (hidden API)
* Make TelephonyManager.getCallState call through to
TelecommManager, to be consistent with
TelephonyManager.ACTION_PHONE_STATE_CHANGED broadcasts for
overall call state. Telephony continues to manage call states for
individual subscriptions.

Bug: 17378767
Change-Id: Ia5e8b21df801ed3af4f6e14c110a72c92f077f88

telecomm/java/android/telecom/TelecomManager.java

@@ -20,6 +20,7 @@ import android.content.Context;
 import android.os.Bundle;
 import android.os.RemoteException;
 import android.os.ServiceManager;
+import android.telephony.TelephonyManager;
 import android.util.Log;
 
 import com.android.internal.telecom.ITelecomService;
@@ -661,11 +662,35 @@ public class TelecomManager {
                 return getTelecomService().isInCall();
             }
         } catch (RemoteException e) {
-            Log.e(TAG, "RemoteException attempting to get default phone app.", e);
+            Log.e(TAG, "RemoteException calling isInCall().", e);
         }
         return false;
     }
 
+    /**
+     * Returns one of the following constants that represents the current state of Telecom:
+     *
+     * {@link TelephonyManager#CALL_STATE_RINGING}
+     * {@link TelephonyManager#CALL_STATE_OFFHOOK}
+     * {@link TelephonyManager#CALL_STATE_IDLE}
+     *
+     * <p>
+     * Requires permission: {@link android.Manifest.permission#READ_PHONE_STATE}
+     * </p>
+     * @hide
+     */
+    @SystemApi
+    public int getCallState() {
+        try {
+            if (isServiceConnected()) {
+                return getTelecomService().getCallState();
+            }
+        } catch (RemoteException e) {
+            Log.d(TAG, "RemoteException calling getCallState().", e);
+        }
+        return TelephonyManager.CALL_STATE_IDLE;
+    }
+
     /**
      * Returns whether there currently exists is a ringing incoming-call.
      *

telecomm/java/com/android/internal/telecom/ITelecomService.aidl

@@ -138,6 +138,11 @@ interface ITelecomService {
      */
     boolean isRinging();
 
+    /**
+     * @see TelecomServiceImpl#getCallState
+     */
+    int getCallState();
+
     /**
      * @see TelecomServiceImpl#endCall
      */

telephony/java/android/telephony/TelephonyManager.java

@@ -2045,7 +2045,11 @@ public class TelephonyManager {
      * Returns a constant indicating the call state (cellular) on the device.
      */
     public int getCallState() {
-        return getCallState(getDefaultSubscription());
+        try {
+            return getTelecomService().getCallState();
+        } catch (RemoteException | NullPointerException e) {
+            return CALL_STATE_IDLE;
+        }
     }
 
     /**
@@ -2142,7 +2146,7 @@ public class TelephonyManager {
         return ITelephony.Stub.asInterface(ServiceManager.getService(Context.TELEPHONY_SERVICE));
     }
 
-    private ITelecomService getTelecommService() {
+    private ITelecomService getTelecomService() {
         return ITelecomService.Stub.asInterface(ServiceManager.getService(Context.TELECOM_SERVICE));
     }
 
@@ -3132,7 +3136,7 @@ public class TelephonyManager {
     @SystemApi
     public void silenceRinger() {
         try {
-            getTelecommService().silenceRinger();
+            getTelecomService().silenceRinger();
         } catch (RemoteException e) {
             Log.e(TAG, "Error calling ITelecomService#silenceRinger", e);
         }